Fluid control device



Sept 26,1939. H. F. LAWRENCE 2,173,881

FLUID CONTROL DEVICE Filed oct. 51, 19:56 s sheets-sheet 1 Sept. 26, 1939. H.. F. LAWRENCE 2,173,831

FLUID CONTROL DEVICE Filed oet. 31, 1956 :s sheets-sheet 2 Sept- 26, 1939 H. F. LAWRENCE V 2,173,881

FLUID CONTROL DEVICE I Filed Oct. 5l, 1936 3 Sheets-Sheet 5 Patented Sept. 26, 1939 UNITED STATES PATENT OFFICE FLUID CONTROL DEVICE Application October 31,

9 Claims.

This invention relates to iiuid control devices, and more particularly to fluid control devices associated with the tuyres of a furnace stoker.

One object of the present invention is to provide a vgenerally improved iiuid control device which is automatic in operation, and which may be readily attached to the tuyres of a stoker.

A more specic object is to provide a fluid control device of a unitary construction comprising a substantially box-like casing adapted for attachment to the end of a tuyre, and a damper element pivotally mounted in said casing.

Another object is to provide improved pivotal mountings for the dampers of fluid control devices which are not subject to binding due to corrosion, dust accumulations, or to the expansion and contraction of the parts, whereby proper operation, as well as longevity of service of the fluid control devices is assured under all conditions of operation.

Other and further objects will become apparent as the description of the invention progresses.

Of the drawings:

Fig. 1 is a longitudinal sectional view taken through one of the retorts of an inclined grate,

multiple retort Stoker of the underfeed type.

Fig. 2 is an enlarged sectional View taken through the upper end of one of the tuyre rows showing an improved fluid control device attached to each of the tuyres thereof.

Fig. 3 is a plan view of a tuyre block showing a pair of uid control devices attached thereto.

Fig. 4 is an end view taken substantially along line 4 4 of Fig. 3, showing the fluid control devices attached to a series of tuyre blocks.

Fig. 5 is a perspective view of one of the iluid control devices comprising the present invention.

Fig. 6 is a perspective View of the iiuid control device shown in inverted position.

Fig. '7 is a plan view of a tuyre block of a slightly modiied construction having a single iiud `control device attached thereto, and

Fig. 8 is an end view taken substantially along line S-B of Fig. "I, showing fluid control devices provided on a series of tuyre blocks.

Referring to the drawings, the numeral I indicates generally a Stoker of the inclined grate, multiple retort, underfeed type, to which, for the purpose of illustration, the fluid control devices comprising the present invention, are applied. Stoker I is of usual construction and comprises a series of alternately disposed retorts 2 and tuyre rows 3. Fuel is supplied to the retorts 2 from a hopper H disposed exteriorly of the front 1936, Serial No. 108,599`

(Cl. 11G- 44) wall 4 of the furnace, and which communicates with a series of cylinders 5 having rams B operating therein, driven by any suitable power mechanism 1. Thus, upon reciprocation of the rams 6 predetermined quantities of fuel are fed to the l Stoker. A series of pushers 8 is provided in the bottom of each retort 2 which underfeed the fuel therealong to extension grates I0 disposed at the lower end of the stoker. The pushers 8 are also actuated by the power mechanism 'I through any A210 suitable link and lever mechanism indicated generally by thev numeral II. Draft air is supplied to the tuyres 3 from a plenum chamber I2 disposed beneath the Stoker, and which in turn is supplied with draft air by any suitable fan or blower mechanism, (not shown) through a passage I3.

Each of the tuyre rows 3 comprises a series of tuyre blocks I4 arrangedv in superimposed stepped relation over the length thereof, each tuyre b-lock consisting of a relatively flat body portion I5, having a forwardly disposed, substantially rectangular air inlet end I5, and a substantially rounded air discharge end I1. Depending from the under side of the body portion I5 adjacent the side edges thereof are a pair of supporting members I8, I8 which in assembly rest upon the side plates I9, I9 of adjacent retorts in a well known manner. Disposed between supporting members I8, I8 and extending longitudinally of the tuyre block from the forward end thereof are a pair rof depending ribs 23 and 2 I. These ribs terminate at their rearwardly disposed ends in an enlarged rib 22 having a substantially rectangular aperture 23 provided therei in. A hook 2li depends from rib 22, and in assembly extends into the aperture 23 of the next lower tuyre block of the series, as shown in Fig. 2, to retain the tuyre ,blocks in position. EX- tending to substantially the discharge end of the f tuyre block I5 from. the rearwardly disposed edge 25 of rib 22 is a relatively narrow rib 26 which, with rib 23 and ribs 20 and 2|, divide the tuyre block in halves. The rearwardly disposed edges 2l and 28 of supporting members i8, I 8 incline outwardly toward the side edges of the tuyre block, while the side edgesk 29 and 3U of rib 22 opposite thereto converge toward rib 23, thereby forming a pair of discharge passages 3| and 32 having restricted throats and diverging side walls. Disposed between edges 2l and 29, and between edges 28 and`30 are a series of ribs 33 which are arranged substantially fan-like in passages 3I and 32, and which` dei-lne a series of passages 34 having restricted inlet ends 35 and '55" iii) diverging side Walls. The forwardly disposed ends of ribs 33 are subtantially arcuate, whereby the throat of the passages 34 are of substantially Venturi construction. The inner forwardly disposed faces 36 and 31 of supporting members I8, I8 form with ribs 2i] and 2| respectively, a pair of inlet passages 38 and 39, which communicates with passages 3| and 32.

In the embodiment of the invention shown in Figs. 3 and 4, a fluid control device 40 is provided for and neatly occupies each of the passages 38 and 39. Each air control device 40, as shown more particularly in Figs. and 6, comprises a casing 4| of substantially box-like construction, having a at upper wall 42 and vertically disposed side walls 43 and 44. Secured to top wall 42 and extending between side walls 43 and 44 near the forwardly disposed ends thereof is a hook 45, which in assembly is adapted to engage the forwardly disposed end of a tuyre block I4.

The bottom of casing 4| is open, as shown in Fig. 6, except that the rearwardly disposed end thereof is provided with a cross sealing strip 45, secured to and extending between side walls 43 and 44, and which, in assembly, rests upon the upper, forwardly disposed end of the next lower tuyre block I4 of the series, as shown in Fig. 2. Mounted on a pair of straps 41 and 48 is a damper element 49. This damper is of the general type shown and described in the pending application of William V. Sauter, and Howard F. Lawrence, Serial No. 22,2117, led on May 18, 1935, and comprises a relatively at, longitudinally extending portion 50 terminating at the rearwardly disposed end thereof in a substantially arcuate portion- 5I which lies in substantially abutting relation with the inner edge 52 of cross strip 48. Portions 59 and 5| extend between side walls 43 and 44, suiiicient clearance being provided to permit vertical movement thereof. When the damper 49 is in fully open position the portion 58 thereof rests upon a pair of supporting lugs 54 and 55 extending inwardly from the lower edges of side walls 43 and 44, as shown in Figs. 2 and 5. The straps 41 and 48 may be constructed of any suitable material, such as of cords or strips of metal, or of non-infiammable compositions, as desired, and are secured at one end to damper 49 in any suitable manner, such as by rivets 59. The other ends of straps 41 and 48 are adjustably secured to a cross strip 51 by means of a clamp bar 53. Cross strip 51 is secured to and extends between the side walls 43 and 44 of casing 4| and the clamp bar 58 is secured thereto by any suitable means, such as by screws 59. Damper 49 may thus be adjusted longitudinally until the arcuate portion 5I thereof lies in substantially abutting relation with the inner edge of cross strip 46. The screws 59 are then tightened and the damper is securely held in adjusted position. It therefore is apparent that when damper 49 is adjusted as just described, into substantially abutting relation with cross sealing strip 46, but little leakage occurs around the end of the damper.

The casing 4|, as well as the damper 49 of the fluid control devices 40, are preferably constructed from sheet metal. As shown in Figs. 5 and 6, the top and side walls, as well as hook 43 and supporting lugs 54 and 55 of the casing 4|, may be formedfrom a single sheet of material. Cross strips 46 and 51 may thenV be readily secured thereto by rivets, spot welding, or by any other suitable means. Damper 49 obviously may also be formed from a single sheet of material, and may be readily assembled in the casing 4|.

From the foregoing description, it is seen that to assemble the fluid control devices 40 upon the tuyre blocks it is only necessary to insert the hooks 45 thereof over the forwardly disposed ends of the tuyres whereupon the devices will assume the position shown in Figs. 2, 3 and 4. Normally the dampers 49 will rest upon the supporting lugs 54 and 55, whereby the rearwardly disposed face of arcuate portion 5| thereof will lie forwardly of the ends of tuyre blocks I4. Thus a passage is defined by the walls 42, 43 and 44 of casing 4| and the top of damper 49, which communi- Cates with the inlet passages 38 or 39 of the tuyre block proper. Thus, the upper surface of each damper 49 is subjected to the pressure of the uid flowing through the associated passage of the tuyre block, while the lower surface thereof, as will be seen upon reference to Fig. 2, is at all times subjected to the pressure of the fluid in plenum chamber l2. It therefore is apparent that when fluid from chamber I2 flows through the tuyre blocks, the dampers associated therewith are subjected to differential pressures, the pressure at the upper surfaces thereof being always less than that applied to their lower surfaces. The dampers 49 are so designed that the dead weights thereof will hold them open so long as the fuel bed overlying the associated tuyre blocks remains at a normal density. However, should a thin spot occur in the fuel bed, thereby reducing the resistance to the flow of air through the tuyre block or tuyre blocks underlying the same, the velocity of the air passing through the latter increases, and as a result the associated dampers are subjected to differential pressures greater than normal. When these differential pressures are sufficient to overcome the weight of the dampers the latter will move upwardly to substantially closed position, thereby shutting off the air ow to the associated tuyre blocks. The combustion rate at such thin portions is thus reduced and they may be built up by the fuel feeding elements to a normal condition again. When such portions again approach a normal condition, thereby imposing a greater resistance to the flow of air through the associated tuyre blocks the differential pressure acting on the associated dampers decreases, and consequently the dampers will move by gravity to open position.

By the construction shown in Figs. 3 and 4, it is seen that the ow of air to both sides of the tuyre blocks is effectively controlled, since in certain cases the density of the fuel overlying one side of the tuyre may be greater than that overlying the other side thereof. Under such conditions the damper associated with the side of the tuyre having the greatest density will remain open, while that associated with the opposite side will close until the fuel bed overlying the same approaches a normal density. Figs. 7 and 8 show an alternative construction wherein but a single air control device 4 8 is provided foreach of the tuyre blocks i4.` Tuyre block i4 is similar in construction to tuyre block I4 except that the intermediate ribs 2@ and 2| have been eliminated therefrom, whereby the rearwardly disposed end I6 between supporting members I8', I8 is relatively smooth at both the upper and lower surfaces thereof. The fluid control devices 40' are identical in construction to the control devices 40 except that they are constructed to extend substantially the entire distance between the inner edges 36 and 31' of '(4 supporting members i8', I8. This construction affords a sin-gle damper element 49' which functions to control the draft air to both sides of the tuyre block- From the foregoing description it is seen that a highly useful, as well as effective iiuid control device has been provided, which is of a unitary construction and may be readily installed on stokers already operating in the field. rI'he control device being constructed to fit tuyre blocks of standard construction, eliminates the necessity of providing special mountngs when it is desired to install air control devices thereon. It is also seen that by providing straps 41 and 48 to pivotally support the dampers the severe conditions under which they operate do not affect the eiciency thereof, since the pivotal mountings are such that any corrosion thereof due to moisture and dust accumulations, do not affect their operation, and as a result the control devices are adapted to operate for long periods of time without requiring attention. However, in the event it should be desired to install new control devices the old ones may be removed and new ones readily substituted therefor without interfering with the adjacent devices.

The specic type of damper employed herein is simply shown for the purpose of illustration, and it is not intended to limit the invention thereto since other forms of dampers may obviously be employed without departing from the invention. It therefore is to be understood that the invention is to be limited only to the scope of the claims which follow.

What is claimed is:

l. In a device of the class described, the combination of a tuyre block adapted to receive fiuid from a source of supply, means provided on said tuyre block defining an inlet passage for fluid, a uid control device detachably secured to said fluid emitting device, said fluid control device comprising a substantially box-like casing communicating with said inlet passage, a damper element pivotally mounted in said casing, one side of said damper element being subjected to the pressure of the fluid in said casing and the other side thereof being subjected to the pressure of the fluid at said source of supply, whereby, when said differential pressure exceeds a predetermined value, said damper element moves to closed position, and one or more longitudinally adjustable straps for pivotally attaching said damper element to said casing.

2. A fiuid control device comprising, a substantially rectangular casing, said casing having topy and side walls, a sealing member extending between said side walls in spaced relation to said top wall` a hook secured to said top wall adapting said casing for attachment to a tuyre block, a cross member secured to said side walls, a damper element provided in said casing, and means for pivotally securing said damper element to said cross member.

3. A fluid control device comprising, a substantially rectangular casing, said casing having top and side Walls, a sealing member extending between said side walls in spaced relation to said top wall, a hook secured to said top wall adapting Said casing for attachment to a tuyre block, a cross member secured to said side walls, a damper element mounted in said casing, and means comprising one or more straps for pivotally securing said damper element to said cross member.

4. A fluid control device comprising, a substantially rectangular casing, said casing having top and side walls, a sealing member extending between said side walls in spaced relation to said top wall, a hook secured to said top wall adapting said casing for attachment to a tuyre block, a cross member secured to said side walls, a damper 5 element provided in said casing, means for pivotally securing said damper element to said cross member, and means provided on said side Walls for supporting said damper in open position.

5. In a device of the class described, the combination of a tuyre block, means provided on said tuyre block defining one or more inlet passages for draft air, a fluid control device operatively associated with each of said passages, each of said fluid control devices comprising a casing, means provided on said casing for detachably securing the same to said tuyre block, and an automatically operable damper pivotally mounted in said casing and extending longitudinally thereof for controlling the fiow of air to said passages.

6. In a device of the class described, the combination of a tuyre block, means provided on said tuyre block defining an inlet passage for iiuid, and a unitary damper mechanism detachably secured to said tuyre block for controlling the flow 0f fluid in said passage, said damper mechanism comprising a casing disposed longitudinally `of said tuyre block and communicating with said inlet passage, a hook secured to said casing and adapted to engage over the end of said tuyre block, and a damper pivotally mounted in said casing and extending longitudinally thereof. l

7. In a device of the class described, the combination of a tuyre block, means provide on said tuyre block defining an inlet passage for draftI air, a damper mechanism for controlling the flow of fiuid in said passage, said mechanism comprisu ing a casing adapted for attachment to said tuyre block, said casing extending longitudinally of said tuyre block and communicationg with said inlet passage, a damper element mounted in said casing and extending longitudinally thereof, and longitudinally adjustable means for pivotally attaching said damper element to said casing.

8. In a device of the class described, the combination of a tuyre block, means provided on said tuyre block defining one or more inlet passages for draft air, a fluid control device mounted on said tuyre block adjacent each of said passages for automatically controlling the fiow of draft air thereto, each of said fluid control devices comprising a casing, means provided on said casing for detachably securing the same to said tuyre block, and a damper element operable by differential pressure pivotaly mounted in said casing and extending longitudinally in respect to the direction of air flow therethrough.

9. In a device of the class described, the combination of a tuyre block, means provided on said tuyre block dening one or more inlet passages for draft air, a fluid control device mounted on said tuyre block adjacent each of said passages for automatically controlling the flow of draft air thereto, each of said iiuid control devices comprising a casing, means provided on said casing for detachably securing the same to said tuyre block, and a damper element operable by differential pressure pivotally mounted in said casing and extending longitudinally in respect to the direction of air flow therethrough, and sealing means disposed at one end of said damper to prevent air leakage to said passage.

HOWARD F. LAWRENCE. 

